maokedon



(Model) S J. J. MAOKEDON.

- SAFETY PLUG AND VALVE FOR BOILERFITTINGS. No.25 6,344. v f PatentedApr. 11,1882.

W c A ATTORNEYS.

N. PETERS. Mum-1pm wanin mn. u. c.

UNITED STATES PATENT OFFICE.

JOHN J. MAOKEDON, OFYOMAHA, NEBRASKA.

SAFETY P LUG AND VALVE F OR BOILER-FITTINGS.

SPECIFICATION forming part of Letters Patent No. 256,344, dated April11, 1882. Application filed August 5, 1881. (Model) To all whom it mayconcern:

Be it known that I, JOHN J. MACKEDON, of Omaha, Douglas county,Nebraska, have inventeda new and Improved Safety .Plug and safety plugand valve for use with gage, heater,

blow-off, steam-gage and water glass cocks, injectors, throttle, check,pop, and safety valves, and all other cocks, valves, and pipes, for thepurpose of automatically cutting off the steam in case such valves orcocks become broken.

In the accompanyingdrawings, Figure l is a longitudinal section of thesafety plug and valve. Fig. 2 is a similar section in a plane at rightangles to Fig. I; and Fig. 3 is a side view, partially sectional, of theseveral parts detached. Fig. 4 is a longitudinal section, showing thecross-pin in the cook or valve that is screwed on the plug.

Similar letters of reference indicate corre sponding parts.

A is the tubular plug, formed with an external thread at one end, sothat it can be tapped into a boiler-plate in the usual manner, andhaving also an external thread at the outer end for attachment of thecook or valve. This form is adapted for locomotive-fittings; but forordinary fittings an internally threaded socket is required in place ofthe external thread to allow use of the plug with such fittings. Theplug may also be formed with the cook or valve, instead of beingseparate therefrom. The aperture of plug A is tapered at the inner endto form the valve-seat.

B is the valve, of tapering form, and provided with a stem, a, thatextends through-an aperture in a guide-yoke, b. The guide-yoke.

may be made of wireor a strip'of metal, and serves to retain the valvecentral. It is attached to a ring, 0, that is fitted in a recess in theend of plug a.

To the inner end of valve'B is attached a wire, d, that extends to nearthe outer end of plug A, where the wire is formed with an eye.

6 is a screw-pin fitted crosswise of plug A,

and passing through the eye of the wire d. The valve and wire areadjusted so that the pin retains the valve off its seat at the inner endof plug A. The valve B being thus held open, the ordinary use of thecook or valve attached to plug A is not interfered with.

In case the cook or other fitting attached to plug A is knocked orbroken off, the projecting end of plug A will also be broken, and thewire d being thus disconnected or released, the steam-pressure willclose the valve to its seat; or, in cases of bending, the wire beingdrawn upon will'draw the valve to its seat.

Instead of the valve B being held open by a cross-pin in plug A, the pinmay be entered in the cock or valve that is screwed on the plug, asshown in Fig. 4. of the drawings. In

this figure, D is a gage-cock screwed on the end of plug A, and e is apin entering at one side'of the cock and passing through the eye of wirecl, which in this case is long enough to extend entirely through plug Ainto the cock 1). The pin a is put in after the cock has been partiallyscrewed to place, so that when'fully in place the valve. will be forcedopen. This gives great facility for the removal of pin 0 to close thevalve B in case the cock is to be taken on".

This safety vah e can be conveniently used to close the plug when it isdesired to remove the fitting for any purpose. In that case it is onlynecessary to remove the pin '6, when the valve will close.

It is evident that this plug and valve can be applied to steam-pipes,check-valves, and other steam-fittings to prevent escape of steam incase of rupture.

Having thus described n1 yinvention, I claim as new and desire to secureby LettersPatent 1. The safety plug and valve for steam fit tings,consisting of plug A, valve B, wire d, and cross-pin e, combined foroperation sub: stantially as shown and described.

2. The guide I) and ring 0, combined with valve 13. and plug A,substantially as and for the purposes set forth.

JOHN JAMES MAOKEDON.

